late bloomer

US /leɪt ˈbluːmər/
UK /leɪt ˈbluːmər/
"late bloomer" picture
1.

a person whose talents or capabilities are not recognized or developed until later than usual

:
He was a late bloomer in his career, finding success in his forties.
Many creative geniuses are often considered late bloomers.
2.

a plant that flowers later in the season than is typical for its species

:
These roses are late bloomers, they won't flower until autumn.
The garden features several beautiful late bloomers that provide color into winter.